Applicants claim priority under 35 U.S.C. xc2xa7119 of Austrian Application No. A 1399/99, filed on Aug. 13, 1999. Applicants also claim priority under 35 U.S.C. xc2xa7365 of PCT/AT00/00219, filed on Aug. 11, 2000. The international application under PCT article 21(2) was not published in English.
The invention relates to a welding system with a welding device and a protective device, in particular a welding shield or a protective guard in the case of welding robots, as well as a method of controlling a welding system with a welding device and protective device and a method of displaying data or images, in particular welding parameters, on a protective shield.
A welding system with a welding device and a protective device, in particular a protective shield for a user, are known, in which the protective device is an electrically controllable protective visor with an activating device and the welding device consists of a power source, a welding torch and a control system. In this type of welding system, the protective visor is independently or automatically darkened, for which purpose a light-sensitive sensor is provided in the visor. When an arc is struck during a welding process, it is detected by the sensor due to the high intensity of light from the arc, whereupon a signal is sent from the sensor to the control system. Current and voltage are then applied by the control system and the protective visor is darkened.
The disadvantage of this system is that in order to initiate darkening of the protective visor, the arc has first to be struck, which means that the user is exposed to the full intensity of the arc for a brief moment, which can cause damage to the eyes of the user or welder.
A welding system and a welding device are also known from DE 296 02 946 U1, in particular a welding shield to shield against a welding process or an arc, in which the protective device is provided in the form of a handle with a protective shield and a transparent visor disposed in the protective shield. The protective device is connected by cable or wire or else wirelessly to an electronically controllable welding current source or a welding device. In order to vary the current strength of the welding current and/or the welding wire feed, a signal transmitter is integrated in the protective device with the handle and the welder is able to operate the signal transmitter without taking his hand off the handle.
The disadvantage of this system is that the protective visor is very dark and in order to take a reading of the settings, the user must lift the visor off his face in order to be able to read the display elements on the welding device and on the welding current source or, not knowing the settings, will enter a setting via the sensor which can lead to welding errors or poor quality weld seams if incorrect welding parameters are set.
A protective device for the eyes is known from JP 09 098395 A, the protective device having a support frame so that it can be attached to a user, in particular the head, and having a protective shield in the region of the user""s face, which is connected to the support frame of an image-generating device which generates a data and/or image display.
Protective devices are also known, in which in order to secure the protective device on the welder, the protective device has a support frame instead of the hand grip, enabling it to be pivotably mounted on the head of the user or welder.
The disadvantage of this is that because the protective visor is so dark, the user or welder has to remove the protective device in order to read the welding settings.
Another significant disadvantage of the known embodiments described above resides in the fact that in order for a user or welder wearing an electronic, controllable protective visor to be able to take a reading of the welding settings without removing the protective device from his face, he has to interrupt or terminate the welding process to switch off the darkening on the protective visor.
A display system and image-generating system for a helmet are described in DE 40 37 879 A1, the display system having a display unit on the inside face of the helmet for displaying information and data. The display light from the display unit is reflected by means of an internal face of the transparent visor disposed on the helmet to an observation position so that a user is able to see a virtual image from inside the helmet.
The disadvantage of this system is that a helmet of this type may not be used for protection purposes in welding processes.
The underlying objective of the invention is to propose a welding system with a welding device and a protective device, in particular a welding shield or a protective cover in the case of welding robots, as well as a method of controlling a welding system with a welding device and a protective device and a method of displaying data or images, in particular welding parameters, on a protective shield such that the user or welder is has unrestricted freedom of movement.
This objective is achieved by the invention due to the features defined in the characterising part of claim 1. The advantage of this system is that the control system initiates and terminates the procedure to darken the protective visor prior to igniting the arc by transmitting a signal, so that the welder, in particular the welder""s eyes, are protected from the arc. Another advantage is the fact that if using wireless signal transmission, there are no restrictions on the movements of the welder.
An embodiment of the type defined in claim 2 is of advantage because the protective device is coupled with the welding system and welding device and it is a simple matter to adapt the darkening procedure to the different welding processes because the degree of darkening can be easily set from the control system, thereby simplifying the circuitry of the activating device for the protective visor in the protective device and bringing a considerable weight saving.
Another embodiment defined in claim 3 is of advantage since it allows the protective device to be used without connecting it to the welding system or welding device.
Advantage is to be had from another embodiment defined in claim 4, because once the welding process has been terminated, in particular once the arc has been switched off, the protective visor is de-activated and the darkening on the protective visor removed.
The objective is also achieved by the invention as a result of the features set out in the characterising part of claim 5. The advantage of this approach is that, even once the protective visor has been darkened, the welder is still able to see the most important welding parameters and adjust a welding parameter without the welding process having to be interrupted in order to be able to read the correction value. Another significant advantage resides in the fact that by generating a virtual data and/or image display, different operating statuses of the welding process may also be displayed to the welder, such as a short circuit, stable arc, arc ignition, etc., enabling the welding process to be accurately monitored and controlled, thereby improving the welding quality.
Claim 6 describes an advantageous embodiment whereby an automatic darkening process can be run and a virtual data and/or image display of the welding parameters and/or the welding process obtained at the same time.
The embodiments defined in claims 7 to 14 also offer advantages since, by using a video camera or an optical recording unit, a virtual image can be generated in real time and an image of the surroundings and/or the welding process will be displayed for the welder in such a way that the image will change depending on the head movement of the welder, obviating the need constantly to remove the protective device.
The invention additionally relates to a method of controlling a welding system with a welding device and a protective device of the type described in the generic part of claim 15.
This objective is achieved by the invention as a result of the features set out in the characterising part of claim 15. The advantage of this system is that it provides a simple means of transferring data and exchanging data between the welding system and the protective device, thereby enabling the darkening switch of the protective device to be controlled depending on the welding process.
The features described in claims 16 to 19 are also of advantage since they ensure that the protective visor is darkened before the arc is ignited and the darkening systemof the protective device can be switched oft once the welding process has ended.
The objective is also achieved by the invention as a result of the features set out in the characterising part of claim 20. The advantage of this system is that by forming a virtual data and/or image display, the welder is able to take readings of specific welding parameters at all times, even if the protective visor is darkened. Another advantage resides in the fact that in welding systems in which the welding device can be placed farther away from the welding point, the welder is able to read the settings via the protective device and will no longer have to run test welds and will no longer have to go backwards and forwards from the welding device.
Finally, the features defined in claims 21 to 23 are of advantage because they give the welder or user the option of being able to display on the protective device those welding parameters which are more important for him.